Good news, Rusty's spot on his nose turned out to mostly be dirt! He had a scab over an almost healed scratch, that was attracting litter dust. Thankful it wasn't anything to really be concerned over, and that the vet didn't laugh at me! LOL
The vet scrubbed his nose with a gauze pad and some peroxide. It looked good for a couple of days, but the dirty spot is returning, just like the vet thought. The sore is healing and putting off some waxy residue that is attracting the dust.
The next morning Rusty decided to be a bit more dramatic and has either ripped a toe nail out or broken it really far down. I can't find the nail when I mess with his foot. He isn't limping, the toe isn't swollen, and he is acting fine, so I'm going to wait and see what happens. Fingers crossed it doesn't get infected. I checked in on him that night because I had left town, and he was resting comfortably. They are so sweet when they are sleeping :)
Well, there you have it...Rusty is a wild child!